Water Changes: can you change out too much?

[Cheeze]

Hi all! Is it possible to cause harm to your system if you change out too much of a % of your water each week? Say for example, 25% ?

I have a 38 gallon breeder style tank that has been cycled for 6 months now, and have been doing 5 gallon (13%) weekly changes with RODI and Red Sea salt. I've been battling brown hair algae for a couple months, and during a recent rock scrubbing stirred up a large amount of "junk" in the water (algae, particles trapped in rocks, detritus, etc...) that I couldn't siphon up fully with a 5 gallon change. So was wondering, if weekly 10 gallon (26%) changes would be too much as I try to clean up more floaters and junk I stir up from rocks and sand?

My CuC consists of about 7 assorted hermits and about 12 assorted snails. The tank is also an AIO with a media tower that I rinse weekly and a skimmer, but I feel the AIO isn't sucking up debris too well. I've considered a stronger return pump to increase the suck-up power to catch more debris, but fear the flow will be too strong.

 

[DaddyFish]

You should be fine with weekly 25% water changes. Most of the established bacteria that matter are on surfaces, not in the water column.

 

[brandon429]

no you can't harm it by the water change, but you can harm it by changing water above a dirty sandbed and upwelling waste.

in bare bottom systems it wouldnt hurt at all to change 100%, this is every pico reef on the planet and they all grow some pretty mad sps. i have a video of mine being drained empty for 33 mins in the air, then refilled with all new water as a demo of water change tolerance in mixed coral systems. its a pico reef. five pounds of live rock and over a decade in corals sit in the air the whole time during the demo.